Pipe joint



Ogt. 11, 1938. c, 0155 2,132,574

PIPE JOINT I Filed oci. 22, 1936 5 I Z .22; /9 20 15 J 50L TON C. MO/SE,

as flfor/zeys.

Patented Oct. 11, 1938 PIPE J OINT Bolton 0. Moise, Pittsburgh, Pa., assignor to National Tube Company, a corporation of New Jersey Application October 22, 1936, Serial No. 107,076

' 1 Claim.

This invention relates to pipe joints and more particularly to a seal or liner therefor.

Many attempts have been made to render pipe joints gas-tight by providing satisfactory seals.

5 Threading requirements and specifications have become extremely rigid but in spite of the fine degree of accuracy with which threads are now formed, it is at present impossible to provide a threaded gas-tight joint.

10 In addition, pipes having non-corrosive linings, particularly copper, have heretofore been used but not extensively,'due to difliculty with the joints. It has been shown that galvanic or electrolytic action between the two unlike metals at 15 the ends of the pipe when contacted with a fluid has quickly destroyed the joints. Various means have been proposed to overcome this, but all of them are imperfect in making a tight seal, and,

moreover, where it is necessary to cut, under serv- 20 ice conditions, the lengths furnished by the factory, the original difficulty is again encountered.

It is accordingly among tne objects of my invention to provide an improved liner or seal for pipe joints.

A further object of my invention is to provide an improved joint for pipes having a non-corrosive lining.

The foregoing and further objects will be apparent after referring to the drawing, in which:

30, Figure 1 is a plan of a preferred embodiment of my improved liner for pipe joints;

Figure 2 isa longitudinal section of the pipe joint of Figure Figure 3 is a longitudinal section of a joint for 35 lined pipe employing the improved liner of the present invention; and Figure-4 is-a longitudinal section of a modified form of liner.

Referring more particularly to the drawing,

40 the numeral 2 designates a preferred embodi ment of the improved liner of the present invention which is preferably made of a soft or plastic metal or an alloythereof. In order to insure the liner seating tightly within the pipe, an annular 45 head or bulge 5 of slightly larger diameter than the inside diameter of the pipe 4 is formed thereon adjacent the inner end byexpanding the liner at that point.

An integral flange 6 is formed on the opposite 50 or outer end of the liner 2. The width of the flange 6 is substantially the same as the wall thickness of the pipe 4 but such that the diameter is no greater than that of the end of the threaded pipe 4. I The flange 6 is broken, as at I, and the 55 periphery has. the form of one turn of a helix of pipe '4.

the same pitch as the pitch of the threads on the One or more inwardly projecting portions 8 may be'provided on the flange 6 adapted to be disposed within depressions or slots 9 in the end of pipe 4. In this manner the liner 2 is fric- 5 tionally held within the pipe 4 by the-annular bead 5 and is positively held against rotation therein by the inwardly projecting portions 8 disposed within the depressions or slots 9. Conseo uently, since the periphery of the flange 6 has 10 the same pitch as the threads of the pipe, the liner 2 being positioned within the end of the pipe 4 with the flange 6 abutting thereagainst, the flange 6 will engage thethreads of the coupling l0 and be advanced, into the coupling ID at the same rate as the pipe 4 when they are screwed together and, due to the taper of the coupling ID, will become securely wedged therein and provide an effective seal.

When used in combination with a pipe having a non-corrosive lining 3 and a coupling made of .a non-corrosive metal or having a non-corrosive lining, the liner, pipe lining, and coupling are formed from metals of such nature that the passage of fluid therethrough will not cause a gal-- vanic or electrolytic action therebetween. Consequently, since the flange 6 closely contacts the threads of the coupling l0 the fluid transmitted cannot contact the unlike metal of the pipe 4. Hence, I am enabled to form a joint for copper lined pipe by use of a copper liner and a coupling preferably of brass that will not. be subject to galvanic or electrolytic action when fluid is passed through the joint and should normally therefore last as long as the non-corrosive lining '35 in the pipe. A joint such as described is shown in Figure 3. Yr

Referring to Figure 4'- of the drawing, a modified form of. the invention is shown 'as comprising an embodiment for use in connection with an 40 oil-well casing. According to this modification, the externally threaded ends ii of the casing are shown as connected by a conventional internally threaded coupling IS. The extremities ll of the casings l5 are. provided with narrow flat portions l8 which extend radially inward from their outside surfaces and adjoin radially, inwardly-extending concaved portions l9' which are provided with one or more detents 20. The liner 22 of this embodiment is shaped to conform to the extremities ll of the "casings l5 and is of the same or slightly greater diameter. This liner 22 is provided with one or more inwardly projecting portions 23 which seat in the detents 20 in the con- 86 ings l5.

While I have shown and described several preferred embodiments of my invention, it will be understood that I do not wish to be limited ex caved portions IQ of the extremities I! of the eassaid pipe, said liner having a radially extending flange at its outer end, said flange being adapted to extend across the end of the wall of said pipe to substantially the crest of the external threads thereon, said flange being split ,to enable the conformation of its periphery to the pitch of the external threads on said pipe, said liner being provided with means for insuring its rotation with said pipe whereby the periphery of the flange of said liner will be deformed into tight sealing engagement with the threads of an internally threaded member to which said externally threaded pipe may be connected.

BOLTON C. MOISE. 

